Carbon sequestration in agriculture for challenging climate change - An overview

Abstract

The world struggles more to address the effect of global warming and changing climatic conditions due to the emission of greenhouse gases (GHGs). Among the GHGs, CO2 is the most dominant gas, compared to methane and nitrous oxide. It accounts for about 50% of the total warming effect of all climate impact gases. One promising technology to reduce the CO2 level in the atmosphere is carbon capture and sequestration (CCS), which consists of capturing CO2 emissions from power plants and industrial sources and sequestering them in deep geologic formations for long periods of time. Carbon sequestration and storage in soils provide an important mean of decreasing GHGs in the atmosphere to mitigate predicted climate changes. Over one third of arable land is in agriculture globally and this will be a major component of using soils as a sink. The carbon sink capacity of the world’s agricultural and degraded soils is 50 to 66% of the historic carbon loss of 42 to 78 gigatons (Gt) of carbon. An increase of 1 ton of soil carbon pool of degraded cropland soils may increase crop yield by 20-40 kg/ha for wheat, 10-20 kg/ha for maize, and 0.5-1 kg/ha for cowpea. As well as enhancing food security, carbon sequestration has the potential to offset fossil fuel emissions by 0.4 to 1.2 Gt of carbon per year, or 5 to 15% of the global fossil-fuel emissions. It is expected that in the next 50 years, Best Management Practices (BMPs) in agriculture could restore 5000 MMTC to the soil. Improved management of crop, grazing, and forest lands is estimated to potentially offset 30,000-60,000 million metric tons of the carbon released by fossil fuel combustion over the next 50 years.